The headset features a flexible solar panel on the headband which captures sun light and stores this energy in 2 Lithium batteries capable of storing 1000 mAh being able to charge 80% of your iPhone 5. The headset features a smart system that will balance the weight of the headphone once energy is stored in them. The headphones can also be charged by USB from your computer.
Here are the full headset specifications:
The solar specification
Here is the demo-video of the headset
You can support this idea by becoming a Baker on its official kickstarter page